Method for preparing lurasidone with high purity and high yieldThe application is a divisional application of an invention patent application with the application number of 201510192142.7 and the application date of 2015, 4-21 and the name of 'a method for preparing high-purity and high-yield lurasidone'.
Technical Field
The invention relates to preparation of a pharmaceutical compound, and in particular relates to a preparation method of lurasidone.
Background
Lurasidone (lurasidone) is a new atypical antipsychotic approved by the Food and Drug Administration (FDA) in 28 u.s.a.2010 for use in treating schizophrenia under the trade name Latuda.
The original patent EP0464846 reports that the synthetic route is that (1R, 2R) -1, 2-bis (methane sulfonic acid oxymethyl) cyclohexane and 3- (1-piperazinyl) -1, 2-benzisothiazole sodium carbonate are refluxed for 23 hours by taking acetonitrile aS a solvent to obtain a condensation compound 1, dimethylbenzene aS a solvent is reacted with (3aR, 4S, 7R, 7aS)4, 7-methylene-1H-isoindole-1, 3(2H) -diketone potassium carbonate in the presence of an 18-crown 6 ether phase transfer catalyst to obtain a condensation compound 2, and the condensation compound is salified to obtain the lurasidone. The reaction time of the route is long, the cost of the used catalyst is high, the toxicity is high, the catalyst is not easy to remove, impurities are easy to generate due to long reaction reflux time, the difficulty of removing the impurities by post-treatment is increased, and the quality of a finished product is not easy to control.
In other related patents or similar routes reported in documents WO2012131606, US20110003994, CN102863437 and the like, the first step of synthesizing the condensate 1 uses acetonitrile or DMF and the like as a solvent, and the reaction time is 20-30h at the reflux temperature (85-150 ℃), so that impurities are easily generated in the high-temperature long-time reaction, and the yield is reduced along with the reduction of the reaction time, and related patents have no reports in terms of quality.
Disclosure of Invention
The invention provides a method for improving the reaction rate of a condensation compound 1 (the reaction time is shortened from 20-30h to 3h), reducing the reaction reflux temperature, effectively controlling the generation of reaction impurities, and obtaining a qualified finished product (related substances are less than 0.1%) through simple post-treatment, so that the method is simple and convenient to operate, has low requirements on environmental protection and is beneficial to industrialization.
The invention provides a method for preparing lurasidone with high purity and high yield, which comprises the following process routes:
(1) reacting (1R, 2R) -1, 2-bis (methane sulfonic acid oxymethyl) cyclohexane with 3- (1-piperazinyl) -1, 2-benzisothiazole in the presence of acetonitrile and sodium carbonate to form a condensate 1;
(2) reacting the condensate 1 with (3aR, 4S, 7R, 7aS)4, 7-methylene-1H-isoindole-1, 3(2H) -diketone to generate a condensate 2;
(3) the condensation compound 2 reacts with hydrochloric acid to generate lurasidone;
wherein step (1) is carried out in the presence of a protic solvent HQ.
Preferably, the first and second liquid crystal materials are,
the protic solvent HQ in the step (1) is selected from CH3OH、C2H5OH、H2One or more mixtures of O;
the feeding molar ratio in the step (1) is (1R, 2R) -1, 2-bis (methane sulfonic acid oxymethyl) cyclohexane: 3- (1-piperazinyl) -1, 2-benzisothiazole: K2CO3Acetonitrile HQ being 1:1.1:1.2, (45-50) and (1-10);
the molar ratio of the feed in step (2) was such that the condensate 1 (3aR, 4S, 7R, 7aS)4, 7-methylene-1H-isoindole-1, 3(2H) -dione was 1: 1-1: 1.3;
the feeding molar ratio in the step (3) is that a condensation compound 2: hydrochloric acid 1: 1-1: 1.4;
the reaction temperature of the step (1) is 75-85 ℃, and the reaction time is 2-4 h;
the reaction temperature of the step (2) is 100-;
the reaction temperature of the step (3) is 50-60 ℃, and the reaction time is 0.5-2 h;
it is further preferred that the first and second liquid crystal compositions,
the feeding molar ratio in the step (1) is as follows: (1R, 2R) -1, 2-bis (Methanesulphonic acid oxymethyl) cyclohexane 3- (1-piperazinyl) -1, 2-benzisothiazole K2CO3Acetonitrile HQ is 1:1.1:1.2:45 (4-6).
It is further preferred that the first and second liquid crystal compositions,
the protic solvent in the step (1) is H2O or CH3OH and H2Mixed solvent of O, CH3OH and H2The molar ratio of O is preferably CH3OH:H2O=1:1-1:0.8。
The invention provides a method for improving the reaction rate of a condensation compound 1, wherein the reaction time is shortened to 3 hours from 20-30 hours of original patent EP0464846 and related patents WO2012131606, US20110003994 and CN102863437, the reaction reflux temperature is reduced, the generation of reaction impurities is effectively controlled, a qualified finished product HPLC (high performance liquid chromatography) can be obtained by simple post-treatment, wherein the HPLC content is more than or equal to 99.0%, and the content of a single impurity is less than 0.1%.
Detailed Description
The invention further refers to the following examples describing in detail the preparation and use of the salts and crystalline forms of the invention. It will be apparent to those skilled in the art that many changes, both to materials and methods, may be practiced without departing from the scope of the invention.
Example 1
A reaction flask was charged with 6g (20mmol) of (1R, 2R) -1, 2-bis (methanesulfonate-oxymethyl) cyclohexane, 4.9g (22.3mmol) of 3- (1-piperazinyl) -1, 2-benzisothiazole and 3.5g (25.3mmol) of potassium carbonate, 50ml of acetonitrile and 1.5g (83mmol) of water were added, the mixture was heated to reflux (82 ℃) and reacted for 3 hours, the reaction was terminated and cooled to room temperature, the inorganic salt was removed by filtration, the solution was concentrated under reduced pressure to the extent that the solvent was removed, 25ml of ethyl acetate was added and stirred to crystallize, the mixture was filtered at 5 ℃ and dried under vacuum to obtain 7.7g of white crystals (condensate 1), 7.7g (yield 91%, HPLC ≥ 98.0%).
Adding 7.7g (18.2mmol) of condensate 1, 4.5g (32.6mmol) of potassium carbonate and 60ml of toluene into a reaction bottle, stirring for 5min, adding 3.2g (19.4mmol) of (3aR, 4S, 7R, 7aS)4, 7-methylene-1H-isoindole-1, 3(2H) -dione, heating to reflux (108 ℃) for reaction for 3H, cooling to room temperature after the reaction is finished, adding 50ml of water, stirring, standing, separating an aqueous phase, adding activated carbon into an organic phase, decoloring for 20min, filtering, concentrating a filtrate under reduced pressure until the solvent is completely removed to obtain a white solid condensate 2, adding 80ml of acetone, stirring, heating to reflux, filtering once while hot, heating the filtrate to reflux, dropwise adding 5ml of 15% hydrochloric acid, stirring, crystallizing, gradually cooling to 5 ℃ and filtering to obtain 7.7g of white crystals (lurasidone) (the yield is 80.1%, HPLC is 99.0%, and the single impurity is less than 0.1%).
Example 2
6g (20mmol) of (1R, 2R) -1, 2-bis (methanesulfonate-oxymethyl) cyclohexane, 4.9g (22.3mmol) of 3- (1-piperazinyl) -1, 2-benzisothiazole and 3.5g (25.3mmol) of potassium carbonate were charged into a reaction flask, 45ml of acetonitrile, 2g (62.5mmol) of methanol and 1g (55.5mmol) of water were added, the mixture was heated to reflux (78 ℃) and reacted for 3 hours, after completion of the reaction, the reaction was cooled to room temperature, inorganic salts were removed by filtration, the solution was concentrated under reduced pressure until the solvent was exhausted, 25ml of ethyl acetate was added and stirred to crystallize, and the mixture was filtered at 5 ℃ and dried under vacuum to obtain 7.6g of white crystals (condensate 1) (yield 89.8%, HPLC ≥ 97.5%).
Adding 7.6g (17.9mmol) of condensate 1, 4.5g (32.6mmol) of potassium carbonate and 60ml of toluene into a reaction bottle, stirring for 5min, adding 3.2g (19.4mmol) of (3aR, 4S, 7R, 7aS)4, 7-methylene-1H-isoindole-1, 3(2H) -dione, heating to reflux (108 ℃) for reaction for 3H, cooling to room temperature after the reaction is finished, adding 50ml of water, stirring, standing, separating an aqueous phase, adding activated carbon into an organic phase, decoloring for 20min, filtering, concentrating a filtrate under reduced pressure until the solvent is completely removed to obtain a white solid condensate 2, adding 80ml of acetone, stirring, heating to reflux, filtering once while hot, heating the filtrate to reflux, dropwise adding 5ml of 15% hydrochloric acid, stirring, crystallizing, gradually cooling to 5 ℃ and filtering to obtain 7.5g of white crystals (lurasidone) (yield 79%, HPLC (99.0% or more, and single impurity (0.1%) 7.5% yield).
Example 3
A reaction flask was charged with 6g (20mmol) of (1R, 2R) -1, 2-bis (methanesulfonate-oxymethyl) cyclohexane, 4.9g (22.3mmol) of 3- (1-piperazinyl) -1, 2-benzisothiazole and 3.5g (25.3mmol) of potassium carbonate, 50ml of acetonitrile and 3.2g (100mmol) of methanol were added, the mixture was heated to reflux (75 ℃) and reacted for 3.5 hours, the reaction mixture was cooled to room temperature after completion of the reaction, the inorganic salt was removed by filtration, the solution was concentrated under reduced pressure to the extent that the solvent was exhausted, 25ml of ethyl acetate was added and stirred for crystallization, and the mixture was filtered at 5 ℃ and dried under vacuum to obtain 7.4g (condensate 1) of white crystals (yield 87.5%, HPLC ≥ 95.0%).
Adding 7.4g (17.5mmol) of condensate 1, 4.4g (31.9mmol) of potassium carbonate and 60ml of toluene into a reaction bottle, stirring for 5min, adding 3.1g (18.8mmol) of (3aR, 4S, 7R, 7aS)4, 7-methylene-1H-isoindole-1, 3(2H) -dione, heating to reflux (108 ℃) for reaction for 3H, cooling to room temperature after the reaction is finished, adding 50ml of water, stirring, standing, separating an aqueous phase, adding activated carbon into an organic phase, decoloring for 20min, filtering, concentrating a filtrate under reduced pressure until the solvent is completely removed to obtain a white solid condensate 2, adding 75ml of acetone, stirring, heating to reflux, filtering once while hot, heating the filtrate to reflux, dropwise adding 5ml of 15% hydrochloric acid, stirring, crystallizing, gradually cooling to 5 ℃ and filtering to obtain 7.2g of white crystals (lurasidone) (the yield is 75.0%, HPLC is 99.0%, and the single impurity is less than 0.1%).